The project will study the use of self-reports as measures of well-being, with a view to advancing the measurement of subjective well-being (SWB) and to advancing the understanding of whether and how such measures can and should be used in policy. Our analysis rests on the distinction between different concepts of happiness. One concept relates to hedonic well-being, the continuous flow of feelings that is experienced on a moment to moment basis. The other is an overall view of how life is going, which comes from a considered judgment. Accumulating evidence suggests that these two concepts capture different aspects of human well- being, and that they respond differently to different circumstances. The project will explore this distinction using large new data sets for the United States and for more than 150 countries around the world. It will look at how the different measures of self-reported well-being are related to life circumstances, with a particular focus on age. There are several hypotheses in economics and psychology about how SWB should change over the life- cycle, and these will organize our investigations. Another major line of investigation is the role of religiosity in well-being; the research will seek to better understand the determinants of religiosity-why people become more religious as they age, why women are more religious than men-as well as the benefits or costs of religion and whether they are or are not universal around the world. The final topic is the extent to which subjective well-being is relative so that, for example, whether well-being depends on a person's own income, or instead on income relative to the income of others. One hypothesis is that the well-known phenomenon of adaptation can often be mistaken for relativity, and that this has important consequences for thinking about economic policy for the elderly, including such issues as the taxation of social security benefits or incentives for postponing retirement. An overarching theme of the work is to understand whether self-reports of well-being can be defended as guides to policy, or whether the criticisms of them by some philosophers and economists are sufficient to rule them out. A better understanding of adaptation is also a key for this last endeavor.